1 //===-- llvm/CodeGen/MachineModuleInfo.cpp ----------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/CodeGen/MachineModuleInfo.h"
11 #include "llvm/ADT/PointerUnion.h"
12 #include "llvm/Analysis/LibCallSemantics.h"
13 #include "llvm/Analysis/ValueTracking.h"
14 #include "llvm/CodeGen/MachineFunction.h"
15 #include "llvm/CodeGen/MachineFunctionPass.h"
16 #include "llvm/CodeGen/Passes.h"
17 #include "llvm/CodeGen/WinEHFuncInfo.h"
18 #include "llvm/IR/Constants.h"
19 #include "llvm/IR/DerivedTypes.h"
20 #include "llvm/IR/GlobalVariable.h"
21 #include "llvm/IR/Module.h"
22 #include "llvm/MC/MCObjectFileInfo.h"
23 #include "llvm/MC/MCSymbol.h"
24 #include "llvm/Support/Dwarf.h"
25 #include "llvm/Support/ErrorHandling.h"
27 using namespace llvm::dwarf;
29 // Handle the Pass registration stuff necessary to use DataLayout's.
30 INITIALIZE_PASS(MachineModuleInfo, "machinemoduleinfo",
31 "Machine Module Information", false, false)
32 char MachineModuleInfo::ID = 0;
34 // Out of line virtual method.
35 MachineModuleInfoImpl::~MachineModuleInfoImpl() {}
38 class MMIAddrLabelMapCallbackPtr final : CallbackVH {
41 MMIAddrLabelMapCallbackPtr() : Map(nullptr) {}
42 MMIAddrLabelMapCallbackPtr(Value *V) : CallbackVH(V), Map(nullptr) {}
44 void setPtr(BasicBlock *BB) {
45 ValueHandleBase::operator=(BB);
48 void setMap(MMIAddrLabelMap *map) { Map = map; }
50 void deleted() override;
51 void allUsesReplacedWith(Value *V2) override;
54 class MMIAddrLabelMap {
56 struct AddrLabelSymEntry {
57 /// Symbols - The symbols for the label.
58 TinyPtrVector<MCSymbol *> Symbols;
60 Function *Fn; // The containing function of the BasicBlock.
61 unsigned Index; // The index in BBCallbacks for the BasicBlock.
64 DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry> AddrLabelSymbols;
66 /// BBCallbacks - Callbacks for the BasicBlock's that we have entries for. We
67 /// use this so we get notified if a block is deleted or RAUWd.
68 std::vector<MMIAddrLabelMapCallbackPtr> BBCallbacks;
70 /// DeletedAddrLabelsNeedingEmission - This is a per-function list of symbols
71 /// whose corresponding BasicBlock got deleted. These symbols need to be
72 /// emitted at some point in the file, so AsmPrinter emits them after the
74 DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >
75 DeletedAddrLabelsNeedingEmission;
78 MMIAddrLabelMap(MCContext &context) : Context(context) {}
80 assert(DeletedAddrLabelsNeedingEmission.empty() &&
81 "Some labels for deleted blocks never got emitted");
84 ArrayRef<MCSymbol *> getAddrLabelSymbolToEmit(BasicBlock *BB);
86 void takeDeletedSymbolsForFunction(Function *F,
87 std::vector<MCSymbol*> &Result);
89 void UpdateForDeletedBlock(BasicBlock *BB);
90 void UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New);
94 ArrayRef<MCSymbol *> MMIAddrLabelMap::getAddrLabelSymbolToEmit(BasicBlock *BB) {
95 assert(BB->hasAddressTaken() &&
96 "Shouldn't get label for block without address taken");
97 AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
99 // If we already had an entry for this block, just return it.
100 if (!Entry.Symbols.empty()) {
101 assert(BB->getParent() == Entry.Fn && "Parent changed");
102 return Entry.Symbols;
105 // Otherwise, this is a new entry, create a new symbol for it and add an
106 // entry to BBCallbacks so we can be notified if the BB is deleted or RAUWd.
107 BBCallbacks.emplace_back(BB);
108 BBCallbacks.back().setMap(this);
109 Entry.Index = BBCallbacks.size() - 1;
110 Entry.Fn = BB->getParent();
111 Entry.Symbols.push_back(Context.createTempSymbol());
112 return Entry.Symbols;
115 /// takeDeletedSymbolsForFunction - If we have any deleted symbols for F, return
117 void MMIAddrLabelMap::
118 takeDeletedSymbolsForFunction(Function *F, std::vector<MCSymbol*> &Result) {
119 DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >::iterator I =
120 DeletedAddrLabelsNeedingEmission.find(F);
122 // If there are no entries for the function, just return.
123 if (I == DeletedAddrLabelsNeedingEmission.end()) return;
125 // Otherwise, take the list.
126 std::swap(Result, I->second);
127 DeletedAddrLabelsNeedingEmission.erase(I);
131 void MMIAddrLabelMap::UpdateForDeletedBlock(BasicBlock *BB) {
132 // If the block got deleted, there is no need for the symbol. If the symbol
133 // was already emitted, we can just forget about it, otherwise we need to
134 // queue it up for later emission when the function is output.
135 AddrLabelSymEntry Entry = std::move(AddrLabelSymbols[BB]);
136 AddrLabelSymbols.erase(BB);
137 assert(!Entry.Symbols.empty() && "Didn't have a symbol, why a callback?");
138 BBCallbacks[Entry.Index] = nullptr; // Clear the callback.
140 assert((BB->getParent() == nullptr || BB->getParent() == Entry.Fn) &&
141 "Block/parent mismatch");
143 for (MCSymbol *Sym : Entry.Symbols) {
144 if (Sym->isDefined())
147 // If the block is not yet defined, we need to emit it at the end of the
148 // function. Add the symbol to the DeletedAddrLabelsNeedingEmission list
149 // for the containing Function. Since the block is being deleted, its
150 // parent may already be removed, we have to get the function from 'Entry'.
151 DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(Sym);
155 void MMIAddrLabelMap::UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New) {
156 // Get the entry for the RAUW'd block and remove it from our map.
157 AddrLabelSymEntry OldEntry = std::move(AddrLabelSymbols[Old]);
158 AddrLabelSymbols.erase(Old);
159 assert(!OldEntry.Symbols.empty() && "Didn't have a symbol, why a callback?");
161 AddrLabelSymEntry &NewEntry = AddrLabelSymbols[New];
163 // If New is not address taken, just move our symbol over to it.
164 if (NewEntry.Symbols.empty()) {
165 BBCallbacks[OldEntry.Index].setPtr(New); // Update the callback.
166 NewEntry = std::move(OldEntry); // Set New's entry.
170 BBCallbacks[OldEntry.Index] = nullptr; // Update the callback.
172 // Otherwise, we need to add the old symbols to the new block's set.
173 NewEntry.Symbols.insert(NewEntry.Symbols.end(), OldEntry.Symbols.begin(),
174 OldEntry.Symbols.end());
178 void MMIAddrLabelMapCallbackPtr::deleted() {
179 Map->UpdateForDeletedBlock(cast<BasicBlock>(getValPtr()));
182 void MMIAddrLabelMapCallbackPtr::allUsesReplacedWith(Value *V2) {
183 Map->UpdateForRAUWBlock(cast<BasicBlock>(getValPtr()), cast<BasicBlock>(V2));
187 //===----------------------------------------------------------------------===//
189 MachineModuleInfo::MachineModuleInfo(const MCAsmInfo &MAI,
190 const MCRegisterInfo &MRI,
191 const MCObjectFileInfo *MOFI)
192 : ImmutablePass(ID), Context(&MAI, &MRI, MOFI, nullptr, false) {
193 initializeMachineModuleInfoPass(*PassRegistry::getPassRegistry());
196 MachineModuleInfo::MachineModuleInfo()
197 : ImmutablePass(ID), Context(nullptr, nullptr, nullptr) {
198 llvm_unreachable("This MachineModuleInfo constructor should never be called, "
199 "MMI should always be explicitly constructed by "
200 "LLVMTargetMachine");
203 MachineModuleInfo::~MachineModuleInfo() {
206 bool MachineModuleInfo::doInitialization(Module &M) {
208 ObjFileMMI = nullptr;
210 CallsEHReturn = false;
211 CallsUnwindInit = false;
212 DbgInfoAvailable = UsesVAFloatArgument = UsesMorestackAddr = false;
213 // Always emit some info, by default "no personality" info.
214 Personalities.push_back(nullptr);
215 PersonalityTypeCache = EHPersonality::Unknown;
216 AddrLabelSymbols = nullptr;
222 bool MachineModuleInfo::doFinalization(Module &M) {
224 Personalities.clear();
226 delete AddrLabelSymbols;
227 AddrLabelSymbols = nullptr;
232 ObjFileMMI = nullptr;
237 /// EndFunction - Discard function meta information.
239 void MachineModuleInfo::EndFunction() {
240 // Clean up frame info.
241 FrameInstructions.clear();
243 // Clean up exception info.
245 PersonalityTypeCache = EHPersonality::Unknown;
250 CallsEHReturn = false;
251 CallsUnwindInit = false;
252 VariableDbgInfos.clear();
255 //===- Address of Block Management ----------------------------------------===//
257 /// getAddrLabelSymbolToEmit - Return the symbol to be used for the specified
258 /// basic block when its address is taken. If other blocks were RAUW'd to
259 /// this one, we may have to emit them as well, return the whole set.
261 MachineModuleInfo::getAddrLabelSymbolToEmit(const BasicBlock *BB) {
262 // Lazily create AddrLabelSymbols.
263 if (!AddrLabelSymbols)
264 AddrLabelSymbols = new MMIAddrLabelMap(Context);
265 return AddrLabelSymbols->getAddrLabelSymbolToEmit(const_cast<BasicBlock*>(BB));
269 /// takeDeletedSymbolsForFunction - If the specified function has had any
270 /// references to address-taken blocks generated, but the block got deleted,
271 /// return the symbol now so we can emit it. This prevents emitting a
272 /// reference to a symbol that has no definition.
273 void MachineModuleInfo::
274 takeDeletedSymbolsForFunction(const Function *F,
275 std::vector<MCSymbol*> &Result) {
276 // If no blocks have had their addresses taken, we're done.
277 if (!AddrLabelSymbols) return;
278 return AddrLabelSymbols->
279 takeDeletedSymbolsForFunction(const_cast<Function*>(F), Result);
282 //===- EH -----------------------------------------------------------------===//
284 /// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the
285 /// specified MachineBasicBlock.
286 LandingPadInfo &MachineModuleInfo::getOrCreateLandingPadInfo
287 (MachineBasicBlock *LandingPad) {
288 unsigned N = LandingPads.size();
289 for (unsigned i = 0; i < N; ++i) {
290 LandingPadInfo &LP = LandingPads[i];
291 if (LP.LandingPadBlock == LandingPad)
295 LandingPads.push_back(LandingPadInfo(LandingPad));
296 return LandingPads[N];
299 /// addInvoke - Provide the begin and end labels of an invoke style call and
300 /// associate it with a try landing pad block.
301 void MachineModuleInfo::addInvoke(MachineBasicBlock *LandingPad,
302 MCSymbol *BeginLabel, MCSymbol *EndLabel) {
303 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
304 LP.BeginLabels.push_back(BeginLabel);
305 LP.EndLabels.push_back(EndLabel);
308 /// addLandingPad - Provide the label of a try LandingPad block.
310 MCSymbol *MachineModuleInfo::addLandingPad(MachineBasicBlock *LandingPad) {
311 MCSymbol *LandingPadLabel = Context.createTempSymbol();
312 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
313 LP.LandingPadLabel = LandingPadLabel;
314 return LandingPadLabel;
317 /// addPersonality - Provide the personality function for the exception
319 void MachineModuleInfo::addPersonality(MachineBasicBlock *LandingPad,
320 const Function *Personality) {
321 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
322 LP.Personality = Personality;
323 addPersonality(Personality);
326 void MachineModuleInfo::addPersonality(const Function *Personality) {
327 for (unsigned i = 0; i < Personalities.size(); ++i)
328 if (Personalities[i] == Personality)
331 // If this is the first personality we're adding go
332 // ahead and add it at the beginning.
333 if (!Personalities[0])
334 Personalities[0] = Personality;
336 Personalities.push_back(Personality);
339 void MachineModuleInfo::addWinEHState(MachineBasicBlock *LandingPad,
341 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
342 LP.WinEHState = State;
345 /// addCatchTypeInfo - Provide the catch typeinfo for a landing pad.
347 void MachineModuleInfo::
348 addCatchTypeInfo(MachineBasicBlock *LandingPad,
349 ArrayRef<const GlobalValue *> TyInfo) {
350 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
351 for (unsigned N = TyInfo.size(); N; --N)
352 LP.TypeIds.push_back(getTypeIDFor(TyInfo[N - 1]));
355 /// addFilterTypeInfo - Provide the filter typeinfo for a landing pad.
357 void MachineModuleInfo::
358 addFilterTypeInfo(MachineBasicBlock *LandingPad,
359 ArrayRef<const GlobalValue *> TyInfo) {
360 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
361 std::vector<unsigned> IdsInFilter(TyInfo.size());
362 for (unsigned I = 0, E = TyInfo.size(); I != E; ++I)
363 IdsInFilter[I] = getTypeIDFor(TyInfo[I]);
364 LP.TypeIds.push_back(getFilterIDFor(IdsInFilter));
367 /// addCleanup - Add a cleanup action for a landing pad.
369 void MachineModuleInfo::addCleanup(MachineBasicBlock *LandingPad) {
370 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
371 LP.TypeIds.push_back(0);
374 void MachineModuleInfo::addSEHCatchHandler(MachineBasicBlock *LandingPad,
375 const Function *Filter,
376 const BlockAddress *RecoverBA) {
377 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
379 Handler.FilterOrFinally = Filter;
380 Handler.RecoverBA = RecoverBA;
381 LP.SEHHandlers.push_back(Handler);
384 void MachineModuleInfo::addSEHCleanupHandler(MachineBasicBlock *LandingPad,
385 const Function *Cleanup) {
386 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
388 Handler.FilterOrFinally = Cleanup;
389 Handler.RecoverBA = nullptr;
390 LP.SEHHandlers.push_back(Handler);
393 /// TidyLandingPads - Remap landing pad labels and remove any deleted landing
395 void MachineModuleInfo::TidyLandingPads(DenseMap<MCSymbol*, uintptr_t> *LPMap) {
396 for (unsigned i = 0; i != LandingPads.size(); ) {
397 LandingPadInfo &LandingPad = LandingPads[i];
398 if (LandingPad.LandingPadLabel &&
399 !LandingPad.LandingPadLabel->isDefined() &&
400 (!LPMap || (*LPMap)[LandingPad.LandingPadLabel] == 0))
401 LandingPad.LandingPadLabel = nullptr;
403 // Special case: we *should* emit LPs with null LP MBB. This indicates
405 if (!LandingPad.LandingPadLabel && LandingPad.LandingPadBlock) {
406 LandingPads.erase(LandingPads.begin() + i);
410 for (unsigned j = 0, e = LandingPads[i].BeginLabels.size(); j != e; ++j) {
411 MCSymbol *BeginLabel = LandingPad.BeginLabels[j];
412 MCSymbol *EndLabel = LandingPad.EndLabels[j];
413 if ((BeginLabel->isDefined() ||
414 (LPMap && (*LPMap)[BeginLabel] != 0)) &&
415 (EndLabel->isDefined() ||
416 (LPMap && (*LPMap)[EndLabel] != 0))) continue;
418 LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j);
419 LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j);
423 // Remove landing pads with no try-ranges.
424 if (LandingPads[i].BeginLabels.empty()) {
425 LandingPads.erase(LandingPads.begin() + i);
429 // If there is no landing pad, ensure that the list of typeids is empty.
430 // If the only typeid is a cleanup, this is the same as having no typeids.
431 if (!LandingPad.LandingPadBlock ||
432 (LandingPad.TypeIds.size() == 1 && !LandingPad.TypeIds[0]))
433 LandingPad.TypeIds.clear();
438 /// setCallSiteLandingPad - Map the landing pad's EH symbol to the call site
440 void MachineModuleInfo::setCallSiteLandingPad(MCSymbol *Sym,
441 ArrayRef<unsigned> Sites) {
442 LPadToCallSiteMap[Sym].append(Sites.begin(), Sites.end());
445 /// getTypeIDFor - Return the type id for the specified typeinfo. This is
447 unsigned MachineModuleInfo::getTypeIDFor(const GlobalValue *TI) {
448 for (unsigned i = 0, N = TypeInfos.size(); i != N; ++i)
449 if (TypeInfos[i] == TI) return i + 1;
451 TypeInfos.push_back(TI);
452 return TypeInfos.size();
455 /// getFilterIDFor - Return the filter id for the specified typeinfos. This is
457 int MachineModuleInfo::getFilterIDFor(std::vector<unsigned> &TyIds) {
458 // If the new filter coincides with the tail of an existing filter, then
459 // re-use the existing filter. Folding filters more than this requires
460 // re-ordering filters and/or their elements - probably not worth it.
461 for (std::vector<unsigned>::iterator I = FilterEnds.begin(),
462 E = FilterEnds.end(); I != E; ++I) {
463 unsigned i = *I, j = TyIds.size();
466 if (FilterIds[--i] != TyIds[--j])
470 // The new filter coincides with range [i, end) of the existing filter.
476 // Add the new filter.
477 int FilterID = -(1 + FilterIds.size());
478 FilterIds.reserve(FilterIds.size() + TyIds.size() + 1);
479 FilterIds.insert(FilterIds.end(), TyIds.begin(), TyIds.end());
480 FilterEnds.push_back(FilterIds.size());
481 FilterIds.push_back(0); // terminator
485 /// getPersonality - Return the personality function for the current function.
486 const Function *MachineModuleInfo::getPersonality() const {
487 for (const LandingPadInfo &LPI : LandingPads)
489 return LPI.Personality;
493 EHPersonality MachineModuleInfo::getPersonalityType() {
494 if (PersonalityTypeCache == EHPersonality::Unknown) {
495 if (const Function *F = getPersonality())
496 PersonalityTypeCache = classifyEHPersonality(F);
498 return PersonalityTypeCache;
501 /// getPersonalityIndex - Return unique index for current personality
502 /// function. NULL/first personality function should always get zero index.
503 unsigned MachineModuleInfo::getPersonalityIndex() const {
504 const Function* Personality = nullptr;
506 // Scan landing pads. If there is at least one non-NULL personality - use it.
507 for (unsigned i = 0, e = LandingPads.size(); i != e; ++i)
508 if (LandingPads[i].Personality) {
509 Personality = LandingPads[i].Personality;
513 for (unsigned i = 0, e = Personalities.size(); i < e; ++i) {
514 if (Personalities[i] == Personality)
518 // This will happen if the current personality function is
519 // in the zero index.
523 const Function *MachineModuleInfo::getWinEHParent(const Function *F) const {
524 StringRef WinEHParentName =
525 F->getFnAttribute("wineh-parent").getValueAsString();
526 if (WinEHParentName.empty() || WinEHParentName == F->getName())
528 return F->getParent()->getFunction(WinEHParentName);
531 WinEHFuncInfo &MachineModuleInfo::getWinEHFuncInfo(const Function *F) {
532 auto &Ptr = FuncInfoMap[getWinEHParent(F)];
534 Ptr.reset(new WinEHFuncInfo);